This invention relates to a process for the preparation of an aerosol type whipping cream with use of CO.sub.2 gas.
In Europe and America, using nitrous oxide or Freon (the tradename by E. I. du Pont) as a whipping agent or propellant, the aerosol type whipping creams are obtained with a good flavor, organoleptic properties and shape-maintaining property.
On the other hand, in Japan the use of these gases in foods is not admitted and gases to be used are limited to CO.sub.2 gas and nitrogen gas. However, the use of CO.sub.2 gas as the whipping agent encounters various difficulties as disclosed in Japanese Patent Publication No. 47-34141. As a result of CO.sub.2 gas dissolving in a sweetened cream the emulsion becomes unstable so that a coagulation or separation of the oil and fat used takes place during the preparation or preservation of products and therefore, good whipping cannot be obtained.
Thus, for overcoming the unstability of the emulsion a self-emulsifying monoglyceride is used for an emulsifier as described in the above Japanese Patent Publication. This self-emulsifying monoglyceride, however, is not suitable for use in foods because of containing potassium or magnesium salts of fatty acids.
For preparing the whipping sweetened cream, solid milk such as a powdered skim milk, fatty acid esters and lecithin are used as the emulsifier or soybean protein is used instead of the solid milk (e.g. Japanese Patent Kokais Nos. 51-70850, 53-98310 and 53-145959).
Sweetened creams using such a solid milk or soybean protein (e.g. an extracted soybean protein or isolated soybean protein) have a good whipping property and shape-maintaining property when whipped with stirring by hand or by machinery.
However, when the whipping cream is charged into an aerosol container and CO.sub.2 gas is fed under pressure and dissolved therein, a good whipping cream cannot be obtained for the reasons that the cream is as a whole too coagulative to be extruded from the container, separation of the oil and fat takes place, and that the cream has rough organoleptic properties.